I don't mean drop them, i mean really lob them like i see in other games. How do you do it?

Only weapon you can really 'lob' is the knife, by pressing the default 'Drop Weapon' key.

Moved to Help/Bugs Section.

so how did luke do it in his vid ?

can you throw weapons straight up?

In order to really "lob" a weapon, it's all about your momentum and release point. Just keep trying different things (jumping while throwing, etc) and you'll get it.